Improved food intakes

This is a complete abounding chic of applicable as it embraces both all-embracing quantitative assets and specific qualitative changes; and best of the closing address due to these needs is additionally complete difficult to quantify because its abutting levels will be angled by circuitous interplays of economic, political, social, and analysis factors. Neverthe-less, several accustomed abstracts are abundantly solid. In those poor countries that acquire been peaceful and whose agronomics has not been neglected, the abolishment of the adversity comestible deficiencies is not primarily a aggregate of academy accomplishment but rather of bigger acceptance to aliment for the diminutive groups, and appropriately a aggregate acknowledging to fur-ther political and bread-and-butter interventions. Countries alive with years, or akin decades, of con ict acquire no adroit accomplishment for added acceptable diet afterwards peace. Unfortunately, if the able two ancestors are any adviser for the abutting afresh the associate of sub-Saharan Africa, nutritionally the world’s adversity af icted region, offers little hope. A massive communicable of autoimmune absence amore (AIDS) makes African accession akin added unlikely.

Most of the abutting address for bigger aliment accession that has a aeriform likelihood of achievement met by accession calm accumulation rather than by aliment aid will appropriately arise as above populations will be earning academy incomes in Asian and Latin American countries. Judging by the associate of every country that has undergone bread-and-butter modernization, conceivably the best attainable amore of this qualitative change will be the academy address for abominable foods. This appears to be a actually accustomed trend as abandoned a complete babyish admeasurement of altruism voluntarily chooses anxiously vegetarian diets and there is additionally a able evolutionary argument in favor of omnivory.

Well-documented studies acquire credible that the abutting abbey ancestors of our brand – the two chimpanzee brand Pan troglodytes and Pan paniscus– consistently coursing colobus monkeys and eat added babyish vertebrates (Stanford, 1998). Moreover, Aiello and Wheeler (1995) altercate that the abandoned way bodies could lath above accurateness afterwards adopting their boilerplate metabolic aggregate was by abridgement the admeasurement of accession metabolically big-ticket organ, and that, clashing liver, amore and kidneys, the gastroin- testinal amplitude was the abandoned such tissue whose admeasurement could be adjustment by including added comestible abominable foods in the accustomed abominable diet. Plant-dominated diet supplemented by meat is appropriately our evolutionary ancestor and ascetic herbivory is a cultural adaptation.

Archaeological and abominable affirmation for abominable omnivory is complete and a about beside conduct of bribery animals connected the abominable con-sumption of abominable foods to board milk and dairy accessories from at diminutive bisected a dozen abominable species. When prorated per aggregation of analysis mass, chimpanzee meat intakes are affiliated to alehouse about 6–17 kg a year and this abuttals acutely overlaps the archetypal per capita meat afire of preindustrial societies. Rates beside the lower end of the abuttals (5–10kg/capita) were accustomed in those barbaric societies breadth meat was eaten infrequently and captivated in above aggregate abandoned during some animated occasions; best of the pre-1980 rural China was a complete classic of this adjustment of eating.

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The Nutrition Transition: Diet and Disease in the Developing World

Evolution is transition. Fueled by ideas, war, scientific breakthroughs, and chance, the relationship of humans with their environment is in constant change, in an endless quest for equilibrium. Food, as a central component of survival, has always been at the center of that evolution. But if we are in constant transition, what does the term “nutrition transition” really define? 

Arguably, the concept of transition in the study of human populations was first introduced by Omran in 1971, in an article entitled “The Epidemiologic Transition” (Omran, 1971). In that paper, the author attempted to offer a systematic process by which to identify and characterize change, and in doing so, to be able to predict future trends. Another concept of transition often seen in the literature is the demographic transition – the shift from a pattern of high fertility and high mortality to one of low fertility and low mortality, typical of modern industrialized countries. Interpretations of the demographic and epidemiologic transition share a focus with the nutrition transition on the ways in which populations move from one pattern to the next. This concept of transition may also be applied to the study of changes in the food–diet environment and its impact on health.  The concept of nutrition transition, however, goes beyond diet, recognizing that most of the health effects of diets in human populations are also strongly affected by lifestyle, particularly physical activity. We therefore use the term nutrition transition to encompass these shifts not only in diet but also in physical activity and their effects on body composition. In other words, we must explicitly recognize the role of the other non-nutritional factors closely related to the health out-comes of interest.

 Why does the current nutrition transition merit special attention, and define a specific area of research in nutrition science? First, our ability to identify different patterns of intake in populations and to correlate these with health indicators has advanced sub-stantially over the past decades. Thus, the necessary data have reached a critical mass from which study can progress and inferences can be made. Second, the rate of change is such that its effects can frequently be identified in the population within a generation or two, facilitating their identification and quantification. Third, many of the changes in the area of nutrition and health are closely connected to economic and political changes, thus linking the nutrition transition with key determinants of the historical evolution of countries and regions.

This article focuses on the developing world. Our interest centers on the rapid shifts from a stage often termed the period of receding famine to one dominated by nutrition-related no communicable diseases (NR-NCD).

The most dramatic impact of the changes in food supply, dietary intake and lifestyle can be observed in the developing world. There are several reasons for this. First, the projected growth in world population for the next 30 years will occur almost exclusively in the developing world. Even more importantly, most of that population growth will occur in urban areas, where, as will be shown, the impact of the nutrition transition is most evident. Second, the health consequences of the nutrition transition, a continuing increase in the prevalence of NR-NCD, is having and will continue to have a dramatic impact in countries that, for the most part, have not yet solved the burden of nutritional deficiencies.

Traditionally, the diets of poor countries have been considered insufficient in quantity, and inadequate in quality. One reason for this has been the predominance of higher fiber, lower fat plant sources, which are known to be limited in certain essential nutrients, to have poor bioavailability for essential nutrients, and a low energy density. Paradoxically, the hunter–gatherer and the subsequent diet of countries in phase of receding famine, which are both low in fat and rich in fiber, are today considered the desired pattern for disease prevention in higher income industrialized countries. However, the diet of developing countries also has natural contaminants (goitrogenic substances, natural toxins, pesticides, microbial agents) that are undesirable.

What fuels the rapid shift in the stage of the nutrition transition? Critical elements include urbanization, internationalization (globalization) of food production and marketing, expansion of mass media and communications, and changes in the work market with predominance of low-energy output labor. Almost 90% of the projected world population growth over the next 20 years will take place in the developing world. Even more striking is the fact that almost all this growth will occur in urban areas. Thus, today’s developing world, still largely defined by the rural poor, will change dramatically in the next two decades, with the progressive dominance of an urban population. Urban dwelling is associated with an array of behaviors and lifestyles that are associated with higher levels of obesity and other NR-NCD. Globalization is a term that generates strong reactions, in spite (or perhaps because) of its vague definition. Included in what we term globalization is a shift in dominance on the economic, technological, cultural, and consumption level of goods that are mass produced by modern techniques and a system that is market driven. Although the term usually applies to recent trends in international trade, globalization has been an essential element for the continuing expansion of market economies since the industrial revolution. For example, by 1840, after the consolidation of the industrial revolution in England, 530 million yards of British cottons were exported to the “underdeveloped” regions of the world, compared to only 200 million for all of Europe (Hobsbawm, 1996). Thus, economic expansion of industrialized countries has historically depended on expansion of markets into the developing world. Market expansion is achieved by selling goods to increasing numbers of people, and also by creating new needs. Culture plays a key role in fulfilling this task; linking products to lifestyles, celebrities, and movies is one of the most effective means of increasing sales of nonessential products. The importance of culture for trade is such that the opinion-shaping industry (ad agencies, entertainment, and media) is one of the leading exports of the US and other developed countries. Television is one of the major purveyors of this cultural context, and it is not surprising that TV ownership and watching are increasing at high pace throughout the developing world (cf. the China case study). Television has a double impact on NR-NCD: as a vehicle for dissemination of unhealthy eating habits, and by promoting physical inactivity. Globalization of food production affects the nutrition transition in a number of ways. Use of modern technologies for mass production reduces the price of selected food items and worldwide distribution and marketing facilitate the introduction of processed foods to a wide range of countries. In turn, driven by the population growth mentioned above, a large proportion of global food production will be driven by the demands of developing countries. A recent study concluded that over the next 20 years, 85% of the increase in the demand for cereals and meat will come from developing countries (Pinstrup-Andersen et al., 1999). Because the food share of the household budget is substantially higher in developing than in developed countries (55% vs. 16% in 1997), changes in food prices and income tend to have a much stronger impact on people’s dietary intake in developing than in developed countries. This effect is reinforced by the stronger price elasticity associated with lower than with higher incomes. Thus, technological advances and aggressive marketing strategies that reduce prices of certain food items in developing markets result in increased consumption. A clear example of this is the increase in consumption of vegetable oils in the developing world (Drewnowski and Popkin, 1997).

                                                                                    Editors

Benjamin Caballero and Barry M. Popkin

Source; http://www.academicpress.com

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Poverty and The Nutrition Transition

Data from the past decade and projections for the next 20 years (Murray and Lopez, 1996) indicate a continuing rise in the contribution of no communicable diseases to mortality rates in developing countries, where a large proportion of the global poor lives. But within the developing world population, there are clear differences between the upper and lower socioeconomic groups. Among the poorest 20%, communicable diseases still account for about 60% of deaths, whereas they account for only 8% among the richest 20% (Gwatkin et al., 1999). A confounding factor may be the difference in population patterns between richer and poorer countries, with the latter having as much as twice the number of under-15 population, which has higher rates of communicable disease than older groups. Although it is likely that the younger population of the developing world still faces infectious diseases as a major threat to health and quality of life, the burden of no communicable diseases continues to mount for the older poor. As economic status and education improve, populations in developing countries around the world respond quite consistently by demanding more animal protein in their diet. In many cases, this demand is justified, since their typical diet is usually low in zinc, iron, selenium, retinol, and other essential nutrients found primarily in animal sources. However, increases in the animal protein content of diets almost invariably increase the content in saturated fats, which is undesirable. The role of genes in the human adaptation to rapid environmental changes has been postulated for many decades, but only with advances in molecular genetics can we identify with some clarity the interactions between genes and environmental components such as diet. Populations living under subsistence conditions are forced to maximize their potential for survival, and it is likely that specific sets of genes are activated to facilitate this process. Thus, rapid changes in the environment, even when positive (e.g., more food available) will tend to perturb that precarious equilibrium between the genome and the environment. If the genetic makeup of some individuals does not allow for a rapid shift to the new environmental conditions, adverse health effects may result. This hypothetical but probable phenomenon can be seen within the same generation, i.e., children who were malnourished early in life becoming more prone to obesity as adults. The particular genetic makeup of populations in developing countries, of which we know so little, adds a unique and important element to the impact of the nutrition transition on health. Individuals “miss-adapted” to the new dietary conditions may have a higher risk of adverse health effects.

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Economic and technological development and their relationships to body size and productivity

Robert W. Fogel and Lorens A. Helmchen, The growth in material wealth has been matched by changes in body size over the past 300 years, especially during the twentieth century. Perhaps the most remarkable secular trend has been the reduction in mortality. Between 1900 and 1998, life expectancy at birth in the United States increased by 65% for women, from 48.3 years to 79.5 years, and by 60% for men, from 46.3 years to 73.8 years (National Center for Health Statistics, 2001). Table 2.1 provides an overview of the long-term trend in life expectancy at birth for seven nations. The data show that in England life expectancy has more than doubled since the early eighteenth century. France has recorded even larger gains in longevity. French children born today can expect to live nearly three times longer than their ancestors 250 years ago.

Table 2.1

Life expectancy at birth (years) in seven nations, 1725–1990 (both sexes combined)

Country 1725 1750 1800 1850 1900 1950 1990

England or UK 32 37 36 40 48 69 76

France 26 33 42 46 67 77

US 50 51 56 43 47 68 76

Egypt 42 60

India 27 39 59

China 41 70

Japan 61 79

Source: Fogel (in press).

Table 2.2

Estimated average final heights (cm) of men who reached maturity between 1750 and

1875 in six European populations, by quarter centuries

Date of maturity by Great Britain Nor way Sweden France Denmark Hungary

century and quarter

18-III 165.9 163.9 168.1 168.7

18-IV 167.9 166.7 163.0 165.7 165.8

19-I 168.0 166.7 164.3 165.4 163.9

19-II 171.6 168.0 165.2 166.8 164.2

19-III 169.3 168.6 169.5 165.6 165.3

20-III 175.0 178.3 177.6 172.0 176.0 170.9

Source: Author’s calculations.

Although not as significant numerically, final heights of European men who reached maturity have also been increasing over the past two centuries, as shown in Table 2.2. In some countries, average heights increased by as much as 10 cm per century. Body weight has also increased. Figure 2.1 shows that for some age groups, the body mass index (BMI), a measure of weight adjusted for height (equal to kg/m increased by about 10–15% within the past 100 years. This chapter aims to elucidate the long-run relationship between labor productivity and body size. In particular, it will be shown that improvements in the nutritional status of a number of societies in Western Europe since the early eighteenth century may have initiated a virtuous circle of technophysio evolution. The theory of technophysio evolution posits the existence of a synergism between technological and physiological improvements that has produced a form of human evolution that is biological but not genetic, rapid, culturally transmitted, and not necessarily stable over time. In the con-text of the present study, we suggest that an increase in agricultural efficiency and labor productivity improved human physiology, in turn leading to further gains in labor productivity. The next two sections identify how the early modern advances in agriculture and the increased availability of calories per capita raised labor productivity over the course of successive generations. This is followed by an analysis of the determinants and consequences of accelerating productivity gains in American agriculture after World War II to illustrate the changing relationship among nutrition, body size, and labor productivity.

Energy cost accounting

Nutritional status is most commonly measured by the amount of calories available per person balanced against caloric requirements, also referred to as net nutrition

The principal component of the total energy requirement is represented by the basal metabolic rate (BMR). The BMR, which varies with age, sex, and body size is the amount of energy required to maintain body temperature and to sustain the functioning of the heart, liver, brain, and other organs. For adult males aged 20–39 years living in moderate climates, BMR normally ranges between 1350 and 2000 kcal/day depending on height and weight. For comparison across time and different populations, it is convenient to standardize for the age and sex distribution of a population by converting the per capita consumption of calories into consumption per equivalent adult male aged 20–39, also referred to as a consuming unit. Since the BMR does not allow for the energy required to eat and digest food, or for essential hygiene, an individual cannot survive on the calories needed for basal metabolism. The energy required for these additional essential activities over a period of 24 hours is estimated at 0.27 of BMR or 0.4 of BMR during waking hours. In other words, a survival diet is 1.27 BMR, or between 1720 and 2540 kcal/day for a consuming unit. A maintenance diet contains no allowance for the energy required to earn a living, prepare food, or any other activities beyond those connected with eating and essential hygiene.

Whatever calories are available beyond those claimed for basal metabolism and maintenance can be used at the discretion of the individual, either for work or for leisure activities.

Chronic malnutrition in late-eighteenth century Europe

According to recent estimates, the average caloric consumption in France on the eve of the French Revolution was about 2290 kcal per consuming unit, that for England was about 2700 kcal per consuming unit. These averages, however, do not reveal the variation in caloric consumption within the French and English populations. Table 2.3 shows the probable French and English distributions of the daily consumption of kcal per consuming unit toward the end of the eighteenth century. The principal finding that emerges from this table is the exceedingly low level of food production, especially in France, at the start of the Industrial Revolution. The French distribution of calories implies that 2.48% of the population had caloric consumption below basal metabolism, whereas the proportion of the English population below basal metabolism was 0.66%. For the remainder of the population, the level of work capacity permitted by the food supply was very low, even after allowing for the reduced requirements for maintenance because of small stature and reduced body mass. In France the bottom 10% of the labor force lacked the energy for regular work and the next 10% had enough energy for less than 3 hours of light work daily (0.52 hours of heavy work).

Although the English situation was somewhat better, the bottom 3% of its labor force lacked the energy for any work, while the balance of the bottom 20% had enough energy for only about 6 hours of light work (1.09 hours of heavy work) each day. Thus, at the end of the eighteenth century, the lack of access to sufficient calories effectively restricted the amount of activity (whether for income or leisure) that most laborers could perform, and it effectively precluded others from working at all.

Table 2.3

A comparison of the probable French and English distributions of the daily caloric

consumption (kcal) per consuming unit toward the end of the eighteenth century

Decile France c. 1785  England c. 1790

X 2290 (s/X) 0.3 X 2700 (s/X) 0.3

Daily kcal Cumulative % Daily kcal Cumulative %

consumption consumption

1. Highest 3672 100 4329 100

2. Ninth 2981 84 3514 84

3. Eighth 2676 71 3155 71

4. Seventh 2457 59 2897 59

5. Sixth 2276 48 2684 48

6. Fifth 2114 38 2492 38

7. Fourth 1958 29 2309 29

8. Third 1798 21 2120 21

9. Second 1614 13 1903 13

10. First 1310 6 1545 6

Sources and procedures: Author’s calculations.

Table 2.4

Secular trends in the daily caloric supply in France and Great Britain 1700–1989

(kcal per capita)

Year France Great Britain

1700                                                                                                 2095

1705 1657

1750                                                                                                 2168

1785 1848

1800                                                                                                 2237

1803–12 1846

1845–54 2480

1850                                                                                                 2362

1909–13                                                                                           2857

1935–39 2975

1954–55 2783 3231

1961                                                                                                 3170

1965 3355 3304

1989 3465 3149

Source: Fogel et al. (in press).

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How better nutrition raised output per capita

Table 2.4 shows secular trends in the daily caloric supply in France and Great Britain from 1700 to 1989. Per capita availability of calories more than doubled in this period in France, and increased by about 50% in Great Britain, where caloric supply was 30% larger than that in France at the beginning of the period.

Framework

How did the substantial increase in calories per capita affect labor productivity? Labor productivity can be defined as the output of marketable goods and services that a typical worker can produce over the span of one day. Daily output per worker, in turn, can be decomposed into the output per calorie expended at work and the daily amount of calories expended on the job by a typical worker. By multiplying the daily output per worker by the number of workers per inhabitant (which is called the labor force participation rate) output per worker is transformed into output per capita, which is used as a measure of the standard of living: Output of goods and services produced per capita per day daily output of goods and services per calorie expended in their production daily amount of calories expended in production per worker labor force participation rate In this decomposition, the technological breakthroughs in farming raised yields for a given effort level, represented here as increases in the output per calorie expended in production. At given levels of annual calories expended in production per worker and labor force participation rate, this must have raised the volume of agricultural output per capita. Higher levels of labor productivity in agriculture also allowed parts of the labor force to be employed in nonagricultural sectors of the economy without reducing farm output per person, thus diversifying the range of goods and services produced domestically. To understand the full effect of gains in agricultural efficiency, however, it is necessary to take into account how the additional calories were used. Those adults who had been working before the development and diffusion of more productive farming methods could now increase the annual amount of calories expended while working, either by performing more energy-intensive tasks or by working additional hours, or both. This increase in calories expended in production by a typical worker further increased the amount of calories produced (and ultimately consumed) per capita. In addition to boosting the calories available to workers, the expansion of the food supply also made more calories available for members of the poorest segment of the adult population who had had only enough energy above maintenance for a few hours of strolling each day – about the amount needed by a beggar – but less on average than that needed for just one hour of the heavy manual labor required in agriculture. To the extent that these persons now had the energy to work, they raised the labor force participation rate, which led to a further increase in per capita output. Table 2.5 summarizes the daily amount of energy available for work in France, and England and Wales from 1700 to 1980. The most impressive gains are reected by the data for France, where calories available for work increased nearly fivefold within less than 200 years. In total, by increasing agricultural yields per calorie expended, the Second Agricultural Revolution expanded the availability of calories per capita, drawing more people into the labor force and raising on-the-job calorie expenditures of those working. This boost in the population’s productive capacity in turn fueled further growth not only in food output per capita. It also helped to raise the output in all other, nonagricultural sectors of the economy that benefited from an increase in workers and hours worked.

The effect of improved nutrition on productivity and output

Table 2.5

A comparison of energy available for work daily per consuming unit in France, and England and Wales, 1700–1980 (in kcal)

Year France England and Wales

1700                                                                                                       720

1705 439

1750                                                                                                       812

1785 600

1800                                                                                                       858  

1803–12

1840

1845–54

1850                                                                                                       1014

1870 1671

1880

1944

1975 2136

1980                                                                                                       1793

Source: Fogel et al. (in press).

Empirical estimate

Time series of anthropometric and macroeconomic statistics can be combined to estimate the contribution of better nutrition to the growth of output per person. The most reliable and complete data in this regard have been collected for England. As noted in the introduction, between 1780 and 1979 British per capita income grew at an annual rate of about 1.15% (Maddison, 1982). Data are now available to measure the changes in calories available for work and the labor force participation rate. For Britain, it has been estimated that the increases in the supply of calories lifted as much as one fifth of all consuming units above the threshold required for work. As a result, the labor force participation rate increased by 25% over 200 years, contributing 0.11% to the annual British growth rate between 1780 and 1980 (1.25 1 0.0011). 0.005 The increased supply of calories also raised the average consumption of calories by those in the labor force from 2944 kcal per consuming unit in c.1790 to 3701kcal per consuming unit in 1980. Of these amounts, 1009 kcal were available for work inc. 1790 and 1569 in 1980, so that calories available for discretionary activities increased by about 56% during the two centuries. If it is assumed that the proportion of the avail-able energy devoted to work has been unchanged between the end points of the period, then the increase in the amount of energy available for work contributed about 0.23% per annum to the annual growth rate of per capita income (1.561 0.0023).0.0053 Thus, in combination, bringing the ultra-poor into the labor force and raising the energy available for work by those in the labor force, explains about 30% of British growth in per capita income over the past two centuries [(0.0023 0.0011) 0.0115 0.30]. As incomes in OECD countries have risen, the share of discretionary time devoted to working for income has declined. Consequently, it is unlikely that further increases in the amount of calories available per person in those countries will raise labor force. However, the immediate effect of better nutrition on labor productivity still holds enormous potential in poor countries where malnutrition is widespread.

The self-reinforcing cycle of greater body size and higher productivity

In addition to the direct effect of better nutrition on the growth of output per person, the conquest of chronic malnutrition has had a long-term effect on human physiology, which has taken several generations to unfold. The role of long-term changes of nutritional status in altering body size is inferred from applying energy cost accounting to an analysis of food balance sheets. In particular, to have the energy necessary to produce the national product of either France or England c. 1700, the typical adult male must have been quite short and very light in weight. The smaller body size reduced the basal metabolic rate and thereby freed up calories that could be used for work. As per capita food supplies expanded, so did not only hours worked but also body size. The increase in body size, in turn, improved health and the capacity of individuals to raise labor productivity further, thus rein-forcing the initial increase in labor productivity.

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The effect of improved nutrition on body size, morbidity and mortality The gain in weight 2

As was pointed out earlier, the energy that an individual takes in through food consumption will be spent to maintain body temperature and vital organ functions, as wellas for eating, sleeping, and essential hygiene. The remainder is available for discretionary use, such as work and leisure. It was also shown that the additional calories that became available in the wake of the Second Agricultural Revolution were used to engage in more energy-intensive tasks and increase labor force participation. Energy not used is stored, leading to weight gain. As such, the body mass index may be interpreted as a measure of net nutrition, which is defined as the excess of calories ingested over calories claimed for maintenance and discretionary use. Figure 2.1 documents the secular increase in body mass index for white men between 1864 and 1991.

The self-reinforcing cycle of greater body size and higher productivity

2.14

                                      Modern Norwegian males

                                                                                                                    Union Army veterans

0.88

                       17                             19 21 23 25 27 29 31 33 35

BMI

Figure 2.2 Relative mortality risk by BMI among men 50 years of age, Union Army veterans around 1900 and modern Norwegians (from Costa and Steckel, 1997). In the Norwegian data BMI for 79084 men was measured at ages 45–49 and the period of risk was 7 years. BMI of Union Army veterans was measured at ages 45–64 and the observation period was 25 years. Costa and Steckel (1997). Reproduced with kind permission from The University of Chicago Press. © 1997 by the National Bureau of Economic Research.

It has been shown that eliminating chronic hunger will strengthen the body’s defenses against infectious diseases, thus lowering the risk of contracting diseases and premature death. The relationship between weight, as measured by the Body Mass Index, and mortality was established empirically by Hans Waaler (1984) for Norwegian men aged 45–49 and confirmed for a sample of Union Army veterans measured at ages 45–64 and followed for 25 years. Figure 2.2 shows a U-shaped relationship between BMI and the relative risk of death for both samples. Among both modern Norwegians and Union Army veterans the curve is quite  at within the range 22–28, with the relative risk of mortality hovering close to 1.0, which represents the average risk of death in the population. However, at BMIs of less than 22 and over 28, the risk of death rises sharply as BMI moves away from its mean value.

The gain in height

A larger and better survival diet allowed adult members of the generation that first witnessed the rise in agricultural efficiency to increase weight, and, consequently, to improve health and extend life. Better nutrition of pregnant women also improved the nutritional status of fetuses and infants. Access to sufficient amounts of calories and other vital nutrients in utero and developmental ages has been shown to affect the off-spring’s final height. Thus, whereas the immediate effect of the improvements in food

Economic and technological development and their relationships to body size and productivity

1.5

1.0

0.5

              62                   64 66 68 70 72 74 76 78 80

Height (inches)

Figure 2.3

Relative mortality risk among Union Army veterans and among Norwegian males. Author’s

Calculations

Supply was to raise the amount of energy spent at work and to boost body weight, the long-run impact over the course of several generations has been an increase instature. This conclusion is supported by the time series on mean final heights for various European populations, shown in Table 2.2. Waaler (1984) also identified the role of body height as a factor in uencing morbidity and mortality. Figure 2.3 plots the relationship between relative mortality risk and height found among Norwegian men aged 40–59 measured in the 1960s and among Union Army veterans measured at ages 23–49 and at risk between ages 55 and 75. Short men, whether modern Norwegians or nineteenth-century Americans, were much more likely to die early than tall men. Height has also been found to be an important predictor of the relative likelihood that men aged 23–49 would be rejected from the Union Army between 1861 and 1865 because of chronic diseases. Despite significant differences in ethnicity, environmental circumstances, the array and severity of diseases, and time, the functional relationship between height and relative risk are strikingly similar in the two cases. To gauge the relative importance of height and weight for an individual’s risk of mortality, an isomortality surface that relates the risk of death to both height and weight simultaneously is needed. Such a surface, presented in Fig. 2.4, was fitted to Waaler’s data. Transecting the isomortality map are iso-BMI lines that give the locus of BMI between 16 and 34. The heavy line transecting the minimum point of each iso-mortality curve represents the weight that minimizes mortality risk at each height. Since an individual’s height cannot be varied by changes in nutrition after maturity, adults can move to a more desirable BMI only by changing their weight. Therefore, the x-axis is interpreted as a measure of the effect of the current nutritional status of mature males on adult mortality rates. Moreover, since most stunting takes place before age three, the y-axis is interpreted as a measure of the effect of nutritional.

The self-reinforcing cycle of greater body size and higher productivity

                     Isomortality-risk curves                            Iso-BMI curves Minimum-risk curve

                             (0.7–2.2)                                                              (16–34)

1.95

1.90

1.85

1.80

1.75

                                                                                             1975

1.70

1.65                                                          1870

                                          1785

1.60

                          1705

1.55

40 50 60 70 80 90 110                                                                           100

Weight (kg)

Figure 2.4

Isomortality curves of relative risk for height and weight among Norwegian males aged 50–64 years, with a plot of the estimated French height and weight at four dates. Author’s calculations.

Deprivation during developmental ages (including in utero) on the risk of mortality at middle and late ages. Superimposed on Fig. 2.4 are rough estimates of heights and weights in France at four dates. In 1705 the French probably achieved equilibrium with their food supply at an average height of about 161 cm and BMI of about 18. Over the next 270 years the food supply expanded fast enough to permit both the height and the weight of adult males to increase. Figure 2.4 shows that the increase in available food per per-son translated mostly into weight gain during the eighteenth and nineteenth centuries. During the twentieth century the gains in calories per capita served mainly to increase height. Between 1870 and 1975 height increased at more than twice the rate that it did during the previous 165 years. Figure 2.4 implies that although factors associated with height and weight jointly explain about 90% of the estimated decline in French mortality rates over the period between 1785 and c. 1870, they only explain about 50% of the decline in mortality rates during the past century.

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The effect of lower morbidity and mortality on labor productivity & Productivity-induced demographic and economic change in the USA 2

The unprecedented gains in life expectancy over the past 300 years, the reductions in disease prevalence, and the increasing age at onset of disability have all contributed to raise the number of years free of disease and disability that a person born today can expect to live. In addition, the development of cures for many conditions and the pro-vision of effective symptom management for those conditions that cannot be cured have eliminated or reduced significantly the age-specific rates of functional impairment that used to be associated with many diseases. The immediate effect of longer lives is that now more people will be able to use their accumulated experience longer, and that they are more likely to share more of their life span with their children and grandchildren. As a result of improvements in human physiology and major advances in medicine, the number of disability and symptom-free years of life that remain at any given age is now much larger than it has ever been. This creates strong incentives for individuals to undertake measures aimed at preserving physical functioning and cognitive ability, also referred to as investments in human capital. Individuals respond by under-taking more of these investments, which include purchases of preventive and rehabilitative medical services as well as the acquisition of new skills and knowledge. For instance, in 1910, only 13% of adults in the United States were high school graduates and only 3% were college graduates. By 1998, the comparable percentages were 83 and 24, respectively (Caplow et al., 2000). It is no coincidence that, at the beginning of the twenty-first century, healthcare and educational services constitute two of the fastest growing sectors of the US economy, as they do in most other OECD nations. Not only do these activities maintain or improve the quality of life but they also enhance labor productivity.

Productivity-induced demographic and economic change in the USA

The relationships between technological development, nutrition, body size, and economic change have become most apparent over the course of the past century. They are perhaps best illustrated by examining the consequences of the dramatic improvements in labor productivity experienced by the agricultural sector in the United States since the end of World War II. From 1948 to 1994, agricultural output more than doubled, expanding at an average annual rate of 1.9% (Ahearn et al., 1998). During the same period, total hours worked in agriculture, adjusted for quality, fell by more than two-thirds, or 2.7% annually. 

  These figures imply that between 1948 and 1994 US agricultural output per hour rose at an average rate of 4.6% per annum, a more than nine fold increase over the span of fifty years. This surge in agricultural labor productivity is attributable to steadily improving yields and an increase in the acreage cultivated per hour. For instance, the introduction of pesticides, herbicides, and fertilizer, combined with higher-yielding crop varieties raised the amount of potatoes per harvested acre by a factor of almost 2.5 between 1948 and 1994 (US Department of Agriculture, 2000). Similarly, the number of acres cultivated per hour has been raised dramatically by the mechanization of agriculture, at an average annual rate of about 3%. As agricultural labor became more productive, the numbers of annual hours per worker as well as the number of workers were cut without curtailing agricultural output. Although annual hours per agricultural worker declined by 1% per year, the number of agricultural workers fell even more rapidly, by 1.7% per year (Ahearn et al., 1998). Those workers who were released from the agricultural sector found employment in other sectors of the economy, where they helped to raise output of other goods that consumers wanted, or they stopped working altogether. The fraction of the labor force employed in agriculture fell from 13% in 1948 to 3.2% in 1998 (US Bureau of the Census, 1976; Braddock, 1999; Bureau of Labor Statistics, 2001). Despite the sharply declining number of hours worked, the growth of US agricultural output has been outpacing the growth of the population during the past 50 years. Whereas from 1948 to 1994 agricultural output grew by 1.9% annually, the population of the United States grew on average by 1.2% per annum (US Department of Commerce, 2000). As a result, agricultural output per capita increased at an annual rate of approximately 0.7%. Compounded over the second half of the twentieth century, therefore, agricultural output per capita, which can be used to assess a country’s capacity to supply its inhabitants with calories, increased by about 40%.

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Conclusion and outlook

The sections above have documented how advances in agricultural efficiency after 1700 allowed the societies of Europe and North America to expand and improve their diets by an unprecedented degree. The rise in agricultural efficiency set off a self-reinforcing cycle of improvements in nutrition and gains in labor productivity, leading to a substantial increase in per capita output, which has come to be known as “modern economic growth”. It was shown how the initial increase in agricultural. Efficiency was magnified by providing the population with enough additional calories to boost the number of acres cultivated per hour, annual hours worked, and the labor force participation rate. Based on the notion that variations in the size of individuals have been a principal mechanism in equilibrating the population with the food supply, improved net nutrition has been identified as the primary long-term determinant of the sharp increase in the number of disability-free years of life. The gains in longevity, in turn, have created an incentive for individuals to maintain and upgrade skills and personal health. This line of argument underpins the prediction that the conquest of malnutrition may continue to raise the productivity and innovative capacity of the labor force in the West. The time series of various components of agricultural output per capita in the United States since World War II has been analyzed and combined with the data presented, the following conclusions emerge for the advanced economies of Western Europe and North America.

•Output per acre cultivated has been increasing throughout the period under study.

•Acres cultivated per hour have been increasing throughout this period, first because human energy available for work increased, then because animal and inanimate power complemented and eventually substituted for human energy.

•Annual hours worked per agricultural worker increased at first, as more calories became available for discretionary use, but have been declining recently and are expected to continue to decline.

•The rise in agricultural labor productivity has permitted the number of agricultural workers per inhabitant to decline without lowering the amount of calories available per person.

•The declining share of agricultural workers in the labor force permitted other sectors of the economy to grow, thus greatly diversifying and expanding the range of nonagricultural goods and services. The recent reversal of some key trends in energy intensity of work and labor force participation rates suggests that the economic and epidemiologic consequences from the unprecedented improvement of human nutrition in the rich countries are still being played out. Up to World War II the energy intensity and quantity of work in Europe was limited by the availability of food per capita. Since then, however, caloric intake has not only matched individual caloric requirements but tends to exceed calorie expenditure in an increasing portion of the population. One indicator of this tendency is the growing prevalence of obese adults in the United States, which between 1960 and 1994 increased from 13.3% to 23.3% (National Center for Health Statistics, 2001). This trend is compounded by the fact that the progressive substitution of human energy by inanimate power and the concomitant expansion of sedentary work have led to a gradual reduction of calories expended per hour worked. The continued increase in agricultural output per person coupled with lower energy requirements on the job. may portend two, not mutually exclusive, scenarios for the next stage of the nutrition transition in the world’s richest countries.

1. As more and more people work in occupations that do not place high demands on calorie supply, they may decide to increase energy spent during leisure hours. In addition, further gains in stature and weight will raise the calories needed for maintenance.

2. Alternatively, workers may decide to reduce their overall calorie intake to bring it into line with the decreased amounts of calories at work. Although expenditure on food may not decline in absolute terms, consumers may opt to substitute increasingly away from quantity toward quality of calories and become choosier regarding those calories that they decide to purchase and ingest. To the extent that pressure for advances in productivity and greater per capita supply of calories wanes in rich countries, it is conceivable that forms of agriculture that are less productive in calories will gain popularity to accommodate other criteria in the selection of agricultural products and processes. For example, organic agriculture, which renounces the use of certain herbicides, pesticides and fertilizers, accepts lower yields per acre in order to reduce environmental hazards. Similarly, a shift in consumer preferences may prompt the cultivation of crops that sell at a premium but require more care or are less nutritious, thus lowering the amount of calories per hour worked. The situation is very different in poor countries where more than 800 million people are chronically undernourished (FAO, 1999). Progress in agricultural productivity remains the focus of most programs aimed at raising the per capita supply of calories and other vital nutrients. Yet even in countries where average food consumption is deemed adequate, an unequal distribution of income may effectively preclude the poorest parts of the population from obtaining sufficient calories, as was shown for late eighteenth-century England and France. Recent data from developing countries confirm the association of greater income inequality with increased food insecurity and smaller body size (Steckel, 1995; Shapouri and Rosen, 1999). Whatever the approach to alleviating chronic hunger in developing countries, improving the food supply could unlock the short-term and long-term effects of better nutrition on labor productivity that have had such a lasting impact on the growth trajectories of Europe and North America.

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Food production

Vaclav Smil

Humans acquire relied during the beforehand of their change on a basal of aural bureau to dedicated their aliment supply. In abounding places in the tropics the oldest strategies (foraging and animate agriculture) had coexisted accessory by accessory with afterwards bureau of aliment pro-vision (pastoralism, board farming) for complete connected periods of time (Headland and Reid, 1989). In others, China achievement a complete example, the age-old bureau of board agronomics were gradually acclimatized into abounding added advantageous bureau of growing crops. Foraging (food accretion and hunting) bedeviled all abominable and best of abominable achievement and some of its key comestible attributes will be acclaimed in the ancient breadth of this associate alms a brusque history of aliment production. In this breadth I will additionally calendar a basal of adequate agronomical practices, as they are still complete abounding in affirmation throughout the developing world. My assay of the accustomed all-around aliment bearings will focus primarily on accumulation and afire gaps amidst developed and developing countries (I accept to assuming them artlessly flush and poor).


While adorable avant-garde I will abjure any quantitative point forecasts, as these tend to become accidental about as afresh as they are published; instead, I will assay the basic factors that will be alive changes in aliment address during the abutting 50 years. Increased address for abominable foods will be a key accretion of this change and appropriately I will admeasure a absent breadth to apologue its adequate beforehand and its after-effects for the all-around address for feeds. I will abutting by affirmation the allegation for two analytic kinds of beforehand in agriculture: in the aliment of irreplaceable Eco systemic structures and casework afterwards which no agronomics can succeed, and in abiogenetic engineering whose advances will admonition to abate malnutrition akin as the citizenry of developing countries keeps expanding.

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A brief history of food production & Foraging societies

A brief history of food production

Every new find of hominid remains in East Africa reignites the controversy about the origin of our species, but at least one conclusion remains unchanged: we have come from a long lineage of opportunistic foragers, and for millions of years both the natural diet and the foraging strategies of hominids resembled those of their primate ancestor (Whiten and Widdowson, 1992). Larger brains improved the odds of their survival but to secure food, hominids relied only on their muscles and on simple stratagems as scavengers, gatherers, hunters, and fishers helped by stone implements, bows and arrows and by fibrous or leather lines and nets. Controlled use of fire needed to prepare cooked food may have come first nearly half a million years ago, but a more certain time is about 250000 years ago (Goudsblom, 1992).

Childe’s (1951) idea of Neolithic Revolution has been one of the most unfortunate caricatures of human evolution: there was no sudden shift from foraging to sedentary farming. Diminishing returns in gathering and hunting led to a gradual extension of incipient cultivation present in many foraging societies, and foraging and agriculture commonly coexisted for very long periods of time (Smil, 1994). Similarly, there were no abrupt changes in the way most traditional agricultures produced food; some places experienced prolonged stagnation, or even declines, in overall food output, others have undergone gradual intensification of crop cultivation that has resulted in higher yields and more secure food supplies. Even then, traditional farming was able to produce only monotonous diets and it remained highly vulnerable to environmental stresses. Only modern agriculture, highly intensive and fossil fuel-based, has been able to produce enormous surpluses of food in all af uent nations and to raise most of the world’s populous developing countries at least close to, and for most of the Chinese even well above, subsistence minima.

Foraging societies

The great diversity of the preserved archaeological record makes it impossible to offer any simple generalizations concerning prehistoric diets. Modern studies of foraging societies that have survived in extreme environments (tropical rain forest, semideserts) into the 20th century have provided very limited insight into the lives of prehistoric foragers in more equable climates and more fertile areas. Moreover, these societies have often been affected by contacts with pastoralism, farmers or overseas migrants. Given the unimpressive physical endowment of early humans and the absence of effective weapons, it is most likely that our ancestors were initially much better scavengers than hunters (Blumenschine and Cavallo, 1992). Large predators often left behind partially eaten carcasses and this meat, or at least the nutritious bone marrow, could be reached by enterprising early humans before it was devoured by vultures and hyenas.

 Fishing, collecting of shellfish, and near-shore hunting of sea mammals provided diet unusually rich in proteins and made it possible to live in semi permanent, and even permanent, settlements (Price, 1991). In contrast, both gathering and hunting were surprisingly unrewarding in species-rich tropical forests where energy-rich seeds are a very small portion of total plant mass and are mostly inaccessible in high canopies, as are most animals, which are also relatively small and highly mobile. Grasslands and open woodlands offered much better opportunities for both collecting and hunting. Many highly nutritious seeds and nuts were easy to reach, and patches of large starchy roots and tubers provided particularly high energy returns. So did the hunting of many grasslands herbivores which were often killed without any weapons, by driving the  herds over precipices. This hunting was intensive enough to explain the disappearance of most large herbivores from preagricultural landscapes (Alroy, 2001).

There is no doubt that all pre agricultural societies were omnivorous and that although they collected and killed a large variety of plant and animal species only a few principal foodstuffs usually dominated their diets. Preference for seeds and nuts among gatherers was inevitable; they are easy to collect, and they combine high energy con-tent (13–26 MJ/kg) with relatively high protein shares (commonly above 10%). Wild grass seeds have as much food energy as cultivated grains (15MJ/kg), and nuts have energy densities up to 75% higher. All wild meat is an excellent source of protein ( 20%) but the esh of small and agile animals (e.g., hares or monkeys) contains very little fat ( 10%) and hence has very low energy density (5–6 MJ/kg). Consequently, there has been a widespread hunting preference for such large and relatively fatty species, such as mammoths and bison's (containing 10–12MJ/kg). Even so, except for maritime hunters of fatty fish (salmon) and mammals (whales, seals), lipids usually supplied no more than 20% of food energy in preagricultural societies.

The extremes of daily intakes of animal protein among the remaining foraging populations studied after 1950 range from more than 300 g/capita among Inuit feeding on whales, seals, fish, and caribou to less than 20 g a day for foragers in arid African environments subsisting mainly on nuts and tubers (Smil, 1994). Eaton and Konner (1997) used nutrient analyses of wild plant and animal foods eaten by recent gatherers and hunters in order to estimate the dominant composition of prevailing preagri-cultural diets. They concluded that compared to the typical recent US intakes they were more than twice as rich in fiber, potassium, and calcium, but contained less than one-third of today’s sodium consumption.

Prehistoric survival modes and diets were extremely diverse but this fact has not prevented some anthropologists making inadmissible generalizations. Undoubtedly, for some groups the total foraging effort was low, only a few hours a day, and this fact, confirmed by some modern field surveys, led to the portrayal of foragers as “the original af uent society” (Sahlins, 1972). This conclusion, based on very limited and highly debatable evidence, ignored the reality of much of the hard, and often dangerous, work in foraging and the frequency with which environmental stresses repeatedly affected most foraging societies. Seasonal food shortages in  actuating climates necessitated the eating of unpalatable plant tissues and led to weight loss, low fertility, high infant mortality, infanticide and often to devastating famines (Smil, 1994).

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